That sense of duty, that feeling of the obligatoriness of the rules of morality, which is so important a principle in human life, and the only principle capable of governing the bulk of mankind, is none other than an acquired reverence for these general principles of conduct, arrived at in the manner described. This acquired reverence often serves as a substitute for the sense of the propriety or impropriety of a particular course of conduct. For many men live through their lives without ever incurring much blame, who yet may never feel the sentiment upon which our approbation of their conduct is founded, but act merely from a regard for what they see are the established rules of behaviour. For instance, a man who has received great benefits from another may feel very little gratitude in his heart, and yet act in every way as if he did so, without any selfish or blameable motive, but simply from reverence for the established rule of duty. Or a wife, who may not feel any tender regard for her husband, may also act as if she did, from mere regard to a sense of the duty of such conduct. And though such a friend or such a wife are doubt- less not the best of their kind, they are perhaps the second best, and will be restrained from any decided dereliction from their duty. Though "the coarse clay of which the bulk of mankind are formed, cannot be wrought to such perfection's as to act on all occasions with the most delicate propriety, there is scarcely anybody who may not by education, discipline, and example, be so impressed with a regard to general rules of conduct, as to act nearly always with tolerable decency, and to avoid through the whole of his life any considerable degree of blame.
Were it not indeed for this sense of duty, this sacred regard for general rules, there is no one on whose conduct much reliance could be placed.
The difference between a man of principle and a worthless fellow is chiefly the difference between a man who adheres resolutely to his maxims of conduct aud the man who acts "variously and accidentally as humour, inclination, or interest chance to be uppermost." Even the duties of ordinary politeness, which are not difficult to ob- serve, depend very often for their observance more on regard for the general rule than on the actual feeling of the moment;and if these slight duties would, without such regard, be so readily violated, how slight, without a similar regard, would be the observance of the duties of justice, truth, fidelity, and chastity, for the violation of which so many strong motives might exist, and on the tolerable keeping of which the very existence of human society depends!
The obligatoriness of the rules of morality being thus first impressed upon us by nature, and afterwards confirmed by reasoning and philosophy, comes to be still further enhanced by the consideration that the said rules are the laws of God, who will reward or punish their observance or violation.
For whatever theory we may prefer of the origin of our moral faculties, there can be no doubt, Adam Smith argues, but "that they were given us for the direction of our conduct in this life." Our moral faculties "carry along with them the most evident badges of this authority, which denote that they were set up within us to be the supreme arbiters of all our actions, to superintend all our senses, passions, and appetites, and to judge how far each of them was either to be indulged or restrained." Our moral faculties are not on a level in this respect with the other faculties and appetites of our nature, for no other faculty or principle of action judges of any other. Love, for instance, does not judge of love, nor resentment of resentment.
These two passions may be opposite to one another, but they do not approve or disapprove of one another. It belongs to our moral faculties to judge in this way of the other principles of our nature. What is agreeable to our moral faculties is fit, and right, and proper to be done; what is disagreeable to them is the contrary. The sentiments which they approve of are graceful and becoming; the contrary ungraceful and unbecoming. The very wordsright, wrong, fit, improper, graceful, unbecoming mean only what pleases or displeases our moral faculties."Since, then, they "were plainly intended to be the governing principles of human nature, the rules which they prescribe are to be regarded as the commands and laws of the Deity, promulgated by those vicegerents which He has thus set up within us." These "vicegerents of God within us" never fail to punish the violation of the rules of morality by the torments of inward shame and self-condemnation, whilst they always reward obedience to them with tranquillity and self- satisfaction.
Having thus added the force of a religious sanction to the authority of moral rules, and accounted for the feeling of obligation in morality, from the physical basis of the pain or pleasure of an instinctive antipathy or sympathy, the philosopher arrives at the question, How far our actions ought to arise chiefly or entirely from a sense of duty or a regard to general rules, and how far any other sentiment ought to concur and have a principal influence. If a mere regard for duty is the motive of most men, how far may their conduct be regarded as right?
The answer to this question depends on two circumstances, which may be considered in succession.